Morphogenetic observations on the marine ciliate Euplotes vannus during cell division (Protozoa: Ciliophora)

2009 ◽  
Vol 90 (4) ◽  
pp. 683-689 ◽  
Author(s):  
Jiamei Jiang ◽  
Chen Shao ◽  
Henglong Xu ◽  
Khaled A.S. Al-Rasheid
Keyword(s):  
Cell Division ◽  
De Novo ◽  
Marine Ciliate ◽  
Daughter Cells ◽  
Euplotes Vannus ◽  
Protozoa Ciliophora ◽  
The Right ◽  
Primary Pattern

Morphogenetic events during the division of the marine ciliate, Euplotes vannus (Müller, 1786) Diesing, 1850 were investigated using protargol impregnation: (1) the opisthe's oral primordium develops de novo in a subsurface pouch above the marginal cirri; (2) the cirral anlagen for the frontal, ventral and transverse cirri in both dividers develop separately on the surface epi-apokinetally, cirrus I/1 and marginal anlagen for daughter cells are formed de novo separately; (3) the dorsal kinety anlagen occur in a non-typical primary pattern within the parental structures at mid-body, of which the 3 right-most ones produce the 3 caudal cirri for the proter; and (4) the opisthe acquires 2 caudal cirri from the end of the right-most 2 kineties. Based on the data available, the reasons for the variation in the number of caudal cirri in E. vannus are discussed.

scholarly journals Spindle-independent condensation-mediated segregation of yeast ribosomal DNA in late anaphase

2005 ◽  
Vol 168 (2) ◽  
pp. 209-219 ◽  
Author(s):  
Félix Machín ◽  
Jordi Torres-Rosell ◽  
Adam Jarmuz ◽  
Luis Aragón
Keyword(s):  
Cell Division ◽  
Ribosomal Dna ◽  
Budding Yeast ◽  
Mitotic Cell ◽  
Yeast Genome ◽  
Daughter Cells ◽  
Late Anaphase ◽  
Mother And Daughter ◽  
The Right ◽  
Chromosome Resolution

Mitotic cell division involves the equal segregation of all chromosomes during anaphase. The presence of ribosomal DNA (rDNA) repeats on the right arm of chromosome XII makes it the longest in the budding yeast genome. Previously, we identified a stage during yeast anaphase when rDNA is stretched across the mother and daughter cells. Here, we show that resolution of sister rDNAs is achieved by unzipping of the locus from its centromere-proximal to centromere-distal regions. We then demonstrate that during this stretched stage sister rDNA arrays are neither compacted nor segregated despite being largely resolved from each other. Surprisingly, we find that rDNA segregation after this period no longer requires spindles but instead involves Cdc14-dependent rDNA axial compaction. These results demonstrate that chromosome resolution is not simply a consequence of compacting chromosome arms and that overall rDNA compaction is necessary to mediate the segregation of the long arm of chromosome XII.

Redescription of the marine ciliate, Certesia quadrinucleata (Protozoa: Ciliophora) from Qingdao, China

2004 ◽  
Vol 84 (6) ◽  
pp. 1131-1136 ◽  
Author(s):  
Xiaofeng Lin ◽  
Weibo Song
Keyword(s):  
Body Shape ◽  
Dorsal Side ◽  
Contractile Vacuole ◽  
Marine Ciliate ◽  
Anterior Edge ◽  
New Information ◽  
Protozoa Ciliophora ◽  
The Right

The living morphology and infraciliature of a marine ciliate, Certesia quadrinucleata, isolated from an abalone-farming pond near Qingdao, China, have been re-investigated, and some new information about this ‘well-known’ species documented: a caudally located contractile vacuole and the highly stable ciliary pattern on dorsal side. Based on previous and present studies, an improved diagnosis is supplied: size 50–90×35–70 μm in vivo; ovoid body shape with a sharp-angled projection on the right anterior edge; adoral zone with 22–27 membranelles and a prominent paroral membrane; 11–12 frontoventral and 4–5 transverse cirri; left marginal row with 5–7 cirri; five dorsal kineties; generally four macronuclear nodules; contractile vacuole positioned at posterior end; marine.

Use of RAPD to detect DNA damage induced by nitrofurazone in marine ciliate, Euplotes vannus (Protozoa, Ciliophora)

2011 ◽  
Vol 103 (3-4) ◽  
pp. 225-232 ◽  
Author(s):  
Liang Zhou ◽  
Jiqiu Li ◽  
Xiaofeng Lin ◽  
Khaled A.S. Al-Rasheid
Keyword(s):  
Dna Damage ◽  
Marine Ciliate ◽  
Euplotes Vannus ◽  
Protozoa Ciliophora

scholarly journals Time-course analysis of nuclear events during conjugation in the marine ciliate Euplotes vannus and comparison with other ciliates (Protozoa, Ciliophora)

Cell Cycle ◽  
2019 ◽  
Vol 18 (3) ◽  
pp. 288-298 ◽  
Author(s):  
Yaohan Jiang ◽  
Tengteng Zhang ◽  
Adriana Vallesi ◽  
Xianyu Yang ◽  
Feng Gao
Keyword(s):  
Time Course ◽  
Marine Ciliate ◽  
Nuclear Events ◽  
Euplotes Vannus ◽  
Protozoa Ciliophora

Observations on Morphogenesis in a marine ciliate Tachysoma ovata (Protozoa: Ciliophora: Hypotrichida)

1999 ◽  
Vol 79 (1) ◽  
pp. 35-38 ◽  
Author(s):  
Weibo Song ◽  
Alan Warren
Keyword(s):  
Cell Division ◽  
Anterior Part ◽  
Marine Ciliate ◽  
Protozoa Ciliophora ◽  
Left And Right ◽  
Definite Period

Divisional morphogenesis of the marine hypotrichous ciliate, Tachysoma ovata was investigated based on protargol impregnated specimens. Its morphogenesis reveals the following peculiarities: (1) there is a definite period during which the anterior part of the newly formed adoral zone of membranelles (AZM) in the opisthe connects with the parental AZM which remains unchanged during the morphogenesis. (2) The anlagen of left and right marginal rows do not develop simultaneously. (3) The replication processes of macronuclear segments are not recognizable during cell division. It is likely that the replication takes place during the interphase. (4) The origin of the fronto-ventral-transverse (FVT) cirral anlagen in the opisthe is characteristic: in other Tachysoma spp. these primordia are generated either from differentiated parental ciliatures (or are orientated by pre-existent organelles), or by division of the proter's FVT-cirral primordia. (5) The primordium of the undulating membranes in the proter always keeps the form of two streaks (so-called ‘semi-anlagen’). There is no conspicuous dedifferentiation or reorganization of the undulating membranes. A morphogenetic comparison with other species of this genus was carried out.

Population dynamics of marine ciliate Euplotes vannus (Protozoa, Ciliophora) in different artificial seawaters

2011 ◽  
Vol 29 (1) ◽  
pp. 109-117 ◽  
Author(s):  
Henglong Xu ◽  
Mingzhuang Zhu ◽  
Yong Jiang ◽  
Shan Gao ◽  
Gi-Sik Min ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Marine Ciliate ◽  
Euplotes Vannus ◽  
Protozoa Ciliophora

scholarly journals CcrZ is a pneumococcal spatiotemporal cell cycle regulator that interacts with FtsZ and controls DNA replication by modulating the activity of DnaA

2021 ◽  
Author(s):  
Clement Gallay ◽  
Stefano Sanselicio ◽  
Mary E. Anderson ◽  
Young Min Soh ◽  
Xue Liu ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Division ◽  
Dna Replication ◽  
Daughter Cells ◽  
Cell Cycle Regulator ◽  
Regulator Protein ◽  
Cytoskeleton Protein ◽  
Initiation Of Dna Replication ◽  
Bacterial Cell Cycle ◽  
The Right

AbstractMost bacteria replicate and segregate their DNA concomitantly while growing, before cell division takes place. How bacteria synchronize these different cell cycle events to ensure faithful chromosome inheritance by daughter cells is poorly understood. Here, we identify Cell Cycle Regulator protein interacting with FtsZ (CcrZ) as a conserved and essential protein in pneumococci and related Firmicutes such as Bacillus subtilis and Staphylococcus aureus. CcrZ couples cell division with DNA replication by controlling the activity of the master initiator of DNA replication, DnaA. The absence of CcrZ causes mis-timed and reduced initiation of DNA replication, which subsequently results in aberrant cell division. We show that CcrZ from Streptococcus pneumoniae interacts directly with the cytoskeleton protein FtsZ, which places CcrZ in the middle of the newborn cell where the DnaA-bound origin is positioned. This work uncovers a mechanism for control of the bacterial cell cycle in which CcrZ controls DnaA activity to ensure that the chromosome is replicated at the right time during the cell cycle.

Sign in / Sign up

Export Citation Format

Share Document